Electric switch.



R. 8. WHITE.

ELECTRIC SWITCH.

APPLHJATION FILED nor. 3!. m4.

1,228,858. Patented June 1917.

r Avsnasts COPY.

ROGER S. WHITE, OF WASHINGTON, DISTRICT OF COLUMBIA.

ELECTRIC SWITCH;

Specification of Letters Patent.

Patented J 11110 5, 1917.

Application filed October 31, 1914. Serial No. 869,598.

pi'fovements in Electric Switches, of which the following is a. specification.

, Ihis invention relates to improvements,

in; switchingor connecting devices for electric circuits. In electric meter test blocks,

'l'or which my invention is especially suited,

a number of terminals and connecting devices are usually exposed m a com paratively restricted space, and in making the changes in the circuits required for cmmeeting in the test meter and then restoring the normal connections of the wires after the meter has been tested, there isalways danger of shock to the [operator in handling the connections, and also danger oi. short circuits from detachable or movable connecting devices being dropped upon or accidentally moved against live terminals. Usually, also with the methods now employed in making meter tests, more of the operatofis time. is required in making the necessary circuit changes than for making the meter tests.

One purpose of my invention is to pro vide a compact switching mechanism which may be assembled upon a meter test block changes in the circuits with a minin'nmr liability to shocks or short circuits, and with a great saving in time over present methods. As very little space is required for operating the switches of my, invention to open and close the circuits, the test l)l()(l\', with its terminals and switchcs, may be made small enough to be placed within the meter easing instead of being arranged outside of the casing on the wall, or in a separate box, as is customary. \Vhile the invention is applicable particularly to meter test blocks, it is also suitable i'or many other purposes, where connections areto be made or broken between dead terminals, or terminals between which there is only a slight difference of potential. In the accompanying drawing, which illustrates my invention,

Figure. 1 is a central section through a switching evice of my invention, showing the same applied to a, panel of insulating material, the terminals for the wires being arranged at one side of the panel and the connecting member at the opposite side;

Fig. 2 is a front view of a portionof the panel, showing two of the switching devices in end view and a. jumper connecting the same;

Fig. 3 aiiother form of switching device embodying my invention, mounted upon a panel, the connecting member being at one side of the panel and the wire tin'minals at the opposite side;

' Fig. 4 is-a front elevation of the connecting plate shown in Fig. 3;

Fig. 5 is a central sectional view through av snitching dcvicc applied to two conducting strips arranged upon the same side of a panel as the connecting device; and

Fig. (3 is a front view of the conducting strips and ctmnection shown in Fig. 5.

Referring to Figs. 1 and 2 of the drawing, 1 represents a slab of insulating material, such as a switchboard panel or the base oi a meter test block, and 2 indicates an opening bored through the. slab for the purpose of permitting one of the connecting devices to extend througln from one. side of the board or slab to the other. As shown. the connecting device comprises av metal bolt 3, threaded'at both ends, a surrounding metal tube 4, shorter than the bolt, and, insulated therefrom by a. tube ol' insulating material 5, the tube l being provided at one end with a metal head (3. which is prel'erably threaded on to the. tube, and the stud or bolt 3 being provided with a threaded metal nut or cup 7, which is adjustable-(n1 the stud into and out of engagement with the head (3 on the tube. A wire terminal H is electrically and mechanically connected to the stud 3 by clamping nuts 9, on the stud. and another wire terminal ll) is electrically and mechanically connected to the surroumling tube 4- by clamping nuts ll. lhe conducting tube land the insulating tube. 5 are held in fixed positions upon the stud 3, between asher 1?), also of insulating material, arranged upon the end 3 of the stud between -the tubes and one ofthe clamping nuts 9.

The cap 7 is hollowed out, as shown at 7",

'60 is a central sectional view through i so that it may extend over and around the clamping nut 12 and engage the head 6 on the tube l. The clamping nut 12 is also of slightly smaller diameter than the tube 4 so and apply the head 6, which holds the entire device in place. The cap 7 is then applied to the stud and the adjustment of this cap into and out of engagement with the head 6 connects or disconnects the bolt with the tube, and hence connects or disconnects the K terminal 8 with the terminal 10. The terminals, it will be seen, are at one side of the panel 1, while the adjustable connecting cap 7 is at the opposite side of the panel. It will ble evident that where the wires and their connecting terminals -arc concealed, either in a casing or at the back of a switch-board, the devices described form a convenient means of connecting and disconnecting the terminals from the outer side of the casing or the front of the board. In Fig. 2, a portion of the front of a board, or the outer wall of a casing, is shown equipped with two of my connecting devices, a and'b, for'the purpose of illustration. It will be noted in Fig. 1 that the head 6 is provided with a groove 6, and in Fig. 2, a jumper wire 14 is shown sprung into the grooves on the members 6 of adjacent switching devices, this being a convenient way of bridgin such adjacent devices, for meter testing, w iere the devices are applied to meter test blocks.

In Fig. 3, the wire terminals 8" and'lO are also at one side of the panel 1, while the cap 7 which makes the electrical connection between these terminals is at the opposite side of the panel. In the form of the invention shown inthis view, the stud 3, upon which the cap7 is mounted, extends throughthe opening 2 in theboard, and the terminal wire connector 8* is connected to the rear end of the stud by clamping nuts 9. The stud has a conical shoulder 3 which abuts against the front of the panel, and it is held in position in the panel by the nuts 9, which draw the shoulder against the panel. Surrounding the conica shoulder 8 is an insulating washer 5, also conical, and a connecting plate 6 also has a conical 0 ening 6 which, when the connector is place upon the front of the board, as shown, receives the washer, .The cap I is adjustable into and out'of engagement with that portion of the connecting plate which surrounds the stud 3 and connects and disconnects the stud. and plate electrically. he plate is heid in post tion by stud 155, which passes through.

threaded opening 6 in the plate and through an opening 2 in the panel, and is provided with a clamping nut 16 at the front side of the panel, and with clampingv nuts 11 at the rear side of the panel, the latter also serving to secure the wire terminal 10" to this stud. It will be evident without further description that the adjustment of the cap 7 will make or break the electrical connection between the terminal's8 and 10. It will also be evident that theseconneotions can be made or broken at the front of the board while the terminals themselves are at the rear.

In Figs. 5 and 6, the invention is shown in connection withconducting bars placed upon the same side of the panel as the cap which connects these bars. In these figures, upon the panel 1", two fiat'conducting bars 8 and 10 are shown, the barshaving overlapping ends. The conductor 10 is secured to the board by'a threaded stud 17 which extends through the board, ands clamping nut 18 fitting on to said stud. The conductor 8 is secured to the board by a threaded screw or stud 3, which passes through the board and has a threaded donnection with said conductor, through which it also extends. The conductor and the stud'are therefore electrically as well as mechanically connected together. The conductor l0 has one end 10 bent outward and overlapping the end of the conductor 8*. This overlapping end of the conductor 10 has one ening 10, through which-the stud 3 exten s, and an insulated bushing 5" fits within this opening and insulates the stud from the corn ductor 10*. An insulating washer 5, which may be integral with or separate from the bushing", separates the overlap ing ends of the two conducting bars 8" an 10". It will be evident that the adjustment of the cap 7 on the stud 3 into and out of engagement with the conductor 10 will make and break the electrical connections between the conductors 10 and 8". While in this instance the conducting bars and the cap for making and breaking the connection between them, are shown on the front of the board, it will be evident also that, for some purposes, wire connections may be ap lied end extending beyond the first mentioned terminal, and a rectal nut having an opening through which said stud extends when the 1:;

nut is at or near its closed position, said nut being adapted to make an annular contact with said first mentioned terminal.

2. In an electric switch, a threaded conducting stud, a conducting tube surrounding and insulated from the stud, said tube having an annular contact surface at one end, and said stud extending outwardly be yond said contact surface, and a connecting member, having a threaded opening therethrough, adjustable on the stud into and out of engagement with said surface. I

3. In an electric switch, a threaded con- "ducting stud, a conducting tube surrounding and insulated from the stud, said tube having a contact surface at one end which surrounds th,. stud, a connecting member, having a threaded opening therethrough, adjustable on the stud into and out of engagement with said surface and adapted to make an annular contact therewith, and attaching devices for conductors on said stud and tube, respectively.

4. A support of insulating material having an opening therethrough, and a switching-device comprising concentric conducting members, insulated from one another and extending through said opening, the outer member having, at one side of the support, a contact surface which surrounds the inner member, and the inner member having, at the same side of the support, a threaded end, projecting beyond said contact surface, a connecting member, having a threaded opening therethrough, adjustable on said threaded end, into andout of engagement with said surface and adapted to make an annular contact therewith, and means on each of said members, at the opposite side of the support, for attaching conductors thereto.

5. In an electric switch, a metal stud, threaded at one end, a metal tube surround ing and insulated from the stud and threaded at the corresponding end, a head fitting the threaded end of the tube and surrounding the same, said stud projecting beyond said head, and a connecting member, having a threaded opening therethrough, threaded on to the stud and adapted to engage said head and make an annular contact there -w ith.

(3. In an electric switch, a metal stud, threaded at both ends, a metal tube shorter .than the stud and surrounding the same,

said tube being insulated from the stud and threaded at both ends, threaded means on corresponding ends of the stud and tube for connecting conductors thereto, and a thread ed head and threaded connecting dev ce at the opposite ends of said tube and stud re- ROGER S. WHITE,

WVitnesses ROBERT WATSON, C. VAN SANT. 

